Refrigeration units for storing perishables such as wine for extended periods of time are known to the art. For example, U.S. Pat. No. 3,500,649 to Feldman discloses a household wine storage chest having a control unit for regulating the inside temperature of the chest to a wine storage temperature of about 55.degree. F., plus or minus 5.degree. F. The chest includes a hinged outer door for allowing access to the chest compartment. A heat barrier is also provided adjacent the door to prevent the escape of cool air from within the compartment. The heat barrier includes circular openings therethrough for accessing individual bottles of wine and also includes removable plugs retained in the openings, around the necks of the stored bottles. For applications in which the chest is subject to widely varying external temperatures, the control unit may be upgraded to include an automatic thermostat to maintain proper temperature at around 55.degree. F.
Another unit, including a modular refrigerated cabinet with removable wine rack is disclosed in U.S. Pat. No. 3,754,408 to Littleton. And in U.S. Pat. No. 3,804,482 to Smith, a wine storage cabinet is disclosed with a refrigerated housing and a plurality of bins for storing a relatively large number of wine bottles. Because of the construction of the cabinet, a thermal gradient is set up between the lowermost portions of the cabinet, adjacent the refrigerated housing, and the uppermost portions of the cabinet. Thus, wine bottles stored at the top of the cabinet experience a slightly higher storage temperature than bottles at the bottom. However, because the storage temperature for red wine is preferably higher than that for white wine, white wine bottles can be stored at the bottom and red wine bottles can be stored at the top. For a wine collection of either solely white or red wine, however, the thermal gradient will cause the storage of some bottles at a preferred temperature and others at a somewhat nonpreferred temperature.
In addition to the above-mentioned refrigeration units for storing wine, a wide variety of other units can be purchased from International Wine Accessories, Inc. ("IWA") of Dallas, Tex. In particular, IWA distributes numerous stand-alone wine refrigeration models, as well as modular wine room systems having capacities of a thousand or more wine bottles. Many of these units offer precise temperature control from 50.degree.-65.degree. F. and humidity control from 50-70% relative humidity. Similar units are also marketed and distributed by The Wine Enthusiast, Inc. of Pleasantville, N.Y. As well known to those skilled in the art of wine preservation, both temperature and relative humidity must be controlled within certain well-recognized limits in order to provide acceptable long term storage. For example, storing wines for extended periods of time at a too high relative humidity can cause the formation of mold on the corks and on the wine labels, thus adversely affecting the aesthetic value of the stored wine. A too low relative humidity can cause the corks to deteriorate by drying out and facilitate the escape of wine during storage.
Each of these above-mentioned examples represents a "dedicated" refrigeration unit for maintaining wine at a predetermined storage temperature. As such, these dedicated units ("wine-coolers") may not be suitable for the storage of perishables other than wine. For example, because wine storage temperatures of 50.degree.-65.degree. F. are significantly higher than those required for the storage of perishables such as milk, vegetables, poultry, etc., the chillers (i.e., compressors) used in wine coolers are typically of relatively lower power-rating when compared to those used in household refrigerators of equivalent size. Accordingly, if a wine enthusiast's collection of wines increases in size, larger wine coolers will typically have to be purchased at the expense of rendering the previously used smaller wine coolers obsolete for the storage of perishables other than wine. In addition, because dedicated wine coolers are typically sold at a significant premium by gourmet and specialty shops, relative to the cost of an ordinary household refrigerator, the cost of storing wine for extended periods of time can be significant.
One attempt to operate a conventional household refrigerator as a wine cooler is disclosed in U.S. Pat. No. 5,060,486 to Linstromberg. Linstromberg discloses a thermostat for providing temperature control of a chilled compartment of a household refrigerator at multiple set-point temperatures. The thermostat includes set-points for off, wine cooler, refrigerator and freezer modes of operation. The set-point temperature for the wine cooler mode is between 55.degree. F. and 60.degree. F. Unfortunately, although a set-point is provided specifically for wine, the refrigerator still regulates the temperature of the chilled compartment in a conventional fashion. Thus, when the thermostat recognizes an unacceptably high compartment temperature, the chiller will turn on and remain running until the set-point temperature is again reached. Unfortunately, as well known to those skilled in the art of wine preservation, cooling wine quickly from a relatively high temperature to the proper storage temperature can adversely affect wine and hinder the efficacy of storing wine for extended periods of time in conventional household refrigerators.
Thus, notwithstanding these developments, there continues to be a need for a device that can be used to convert a conventional refrigerator into an economical cooler for storing wine and like perishables in a preferred manner for extended periods of time. There also continues to be a need for a device that is readily interchangeable between refrigerators of different size to allow for the expansion of a wine enthusiast's collection, without rendering a previously used refrigerator obsolete for other than wine storage use.